The recent widespread growth of feature-rich, relatively portable, and user-friendly consumer electronic devices has sparked a corresponding consumer demand for implementation of similar functionality in conventional appliances and utilitarian devices. For example, more consumers are demanding modern touchscreen interfaces in utility appliances like televisions, refrigerators, dishwashers, and washing machines. Even modern thermostats are integrating gesture-controllable, fully-networked and remotely accessible user interfaces (UIs). Even the automobile, often thought of as the quintessential utilitarian machine, has not been impervious to recent trends to incorporate as many options and features accessible to the driver as possible—from mechanical switch controls for climate, navigation, and radio systems integrated into the steering wheel, to touchscreen interfaces and camera displays integrated into the dashboard.
Although consumer demand for incorporating greater functionality into the automotive driving experience is growing rapidly, there are a number of problems with meeting such demand. First, conventional capacitive sense touchscreen technologies, such as those used in smartphones and tablet devices, while ideal for incorporating a large amount of functionality in a relatively limited space, require significant visual engagement by the driver and are therefore too distracting to be implemented safely. Second, while the conventional mechanical switches and knobs that are currently in use are less distracting because they can be safely used without requiring the driver to remove his eyes from the road, they tend to have limited flexibility, with each switch controlling a single function or feature.
One solution for combining the flexibility and versatility of touchscreen technologies while still allowing the driver to remain attentive for safely operating the vehicle involves the use of force-based haptic human-machine interfaces (HMIs). Force-based haptic HMIs typically include a sensor surface that is responsive to touch and an actuator for generating a responsive vibration (often simulating the response provided by a mechanical switch) that provides the driver with a tactile confirmation of an input on the touchscreen. These systems incorporate the haptic feedback that drivers have come to rely on of mechanical switches with the multi-touch, multifunction flexibility of touchscreen controls.
One problem with touch-based haptic HMIs is that the mechanical energy produced by a haptic actuator that is embedded within the switch panel is often dampened by the internal structure of the switch panel. This problem is exacerbated by the fact that such actuators are typically not in close proximity to the touch surface. Thus, in order to ensure that the haptic feedback is perceptible by the user, the haptic actuator needs to generate a signal that is large enough to compensate for the energy lost due to absorption by the system. Ensuring power levels that are sufficient to compensate for internal mechanical absorption may be adequate in mechanically static environments, like mobile phones and tablets. However, such a solution may be insufficient in mechanically dynamic environments, such as automobiles, where mechanical vibrations in the system further compound the problem of user perceptibility of haptic feedback.
The presently disclosed an apparatus and method for facilitating direct delivery of haptic energy to a touch surface of the tactile haptic switch panel are directed to overcoming one or more of the problems set forth above and/or other problems in the art.